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dug_junk
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Amp/Preamp options are killing me...

I'm making my first foray into the high(er)-end audio world and I'm now mostly convinced that once I hook up my new sweet speakers (www.tyleracoustics.com, Linbrook Sig monitors) that it is going to sound like my hand-me-down Kenwood surround stereo is powered by a diesel engine, my CD player will sound like finger nails on a chalk board, and that the sound will be so terrible as to offend even my neighbors in their own homes. Seriously.

So I'm considering a few options. 1)Wait it out and try the Kenwood receiver. I know it won't have enough power to run the speakers to their full potential. I'll likely do this anyway, since it won't cost any extra. 2) Find a good new/used integrated amp, and 3) Find a good new/used pre-amp and power the speakers with some monoblock amps used to power the same speakers in a friend's setup (IRD audio MB-100's).

So here is an actual question:

I'm looking at preamps more then integrated. For a new unit, I'm considering a NAD C162. I've also been purusing online used resources and have seen some used equipment that may be good in a similar price range (about $400-600). Perhaps a Classe DR-5. Am I better off buying the NAD (new or maybe an old, cheaper model) to get started, or spend a little more on a better used unit?

I don't even like asking that question. I know it's such a subjective topic, but I think my head is going to pop, so I thought I would fire off a question before I get my keyboard all messy. Thanks. I feel a little better already.

Are you still with me? I feel a little like I'm venting, since I don't have a good sounding board in the way of a local hi-fi store. So I'll say that I'm willing to hear any advice or direction in the way of good resources. Especially local sources in the Cleveland, OH area. Thanks for reading.

Monty
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Re: Amp/Preamp options are killing me...

Yeah, the choices are simply endless. Sometimes you have to take a step back and put pen to paper.

Seriously, I would start making a list of things that I need in a preamp. How many inputs am I going to need to run all the gear I intend to use? Is a turntable in the future? Will I be upgrading in the next couple of years or do I want this choice to be a lasting one? Do I want to try a tube preamplifier (tube preamps are virtually maintenance free as opposed to tube amps) or stick with solid state?

After making a list of things I need in a preamp, the choices narrow. From there, the question becomes whether to go for new (warranty!) or used (dicey, but more performance for the money).

Nobody can tell you what will work best for you, but if it were me, I would buy an integrated and only go separates if I had a larger budget. Perhaps look for an integrated that has a pre-out option that would allow you to use only the preamp section should you eventually want to try separates.

Someone else on here recently opted for the Outlaw 2150 receiver that does have a pre-out, though it already pumps out gobs of power. Well reveiwed, btw.

Scooter123
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Re: Amp/Preamp options are killing me...

I looked up the specs for those speakers of yours. They are specified as being 4 ohm speakers with an efficiency of 92 db. That's a good news/bad news combination.

I also saw they sell for 5500 USD per pair and I sort of question your budget decision in buying such an expensive speaker. If you haven't totally commited to those speakers you may want to look into some less expensive speakers so you have more room in your budget for other components. However, it's your decision and I do understand why you might want to get as good a speaker as possible from the start and then build the rest of the system over time.

The good news is that at 92 db efficiency they won't need as much power as a speaker with lower efficiency. BTW, the average efficiency runs around 87 to 89 db.

The bad news is the 4 ohm impedence. That means that you should be shopping for a "high current" amplifier. Which basically eliminates any "consumer" reciever typically sold at the Big box stores.

In theory you should really be shopping for an amplifier that is rated to deliver at loads as low as 2 ohms. Which means that you'll probably end up looking at monobloc amplifiers like those offered by Krell or Threshold BUT it may not really be necessary. That 92 db efficiency may just let you squeak by with an amplifier rated for 4 ohms. BTW, a speaker that's rated at 4 ohms won't have a 4 ohm impedence across the entire frequency spectrum, it will probably dip to 2 ohms or a bit less at a few points in the spectrum. If your cranking the system to house shaking volumes, that 2 ohm impedence may cause the power supply in the amplifier to fall short, which will means it will sound lousy or trigger the protection circuitry. The good news is that if you don't need to "max out" the amplifier, an amplifier rated for 4 ohms may have enough in reserve to handle those 2 ohm dips. So an amplifier that's rated for 4 ohms that has enough wattage will have enough "reserve" to handle a 2 ohm dip at reasonable listening levels.

Basically, I would look for an amplifier that's rated for at least 100 wpc with both channels driven into an 8 ohm load. With a variable current amplifier that means that it will probably be rated for 200 watts at 4 ohms. However, keep in mind that a low impedence speaker will draw more current and this means that the amplifier will run hotter than it would with 8 ohm speakers. Which means that cooling will be CRITICAL. Don't stack anything on top of that amp and put some spacers under the feet so that air can flow freely thru the amplifier. If you don't, you could over heat that amp and shorten it's lifespan by a huge amount. MY rule of thumb for amps is 2 inches under the amp and at least 6 inches above the amp to guarantee free air flow.

Now, about that Kenwood. Being a surround sound reciever I expect that it's a typical "consumer" reciever. Which means that it's rated to deliver it's output power with only ONE channel driven. That means that the power supply may not have enough capacity to drive both your speakers at full volume. If so, you'll probably find that turning up the volume too much will trigger the protection circuitry built into the reciever. Basically, try it and see what happens.

As for suggestions, I'll name a few integrated amps at various price points. BTW, I favor integrated amps simply because they reduce the clutter by a huge amount and your guaranteed of getting a pre amp that's perfectly matched to your amplifier.

First and cheapest, the NAD C372. It's rated for 170 wpc at 8 ohms (continuous) and 340 wpc at 4 ohms (this is a music power rating). Cost is about 900 USD and it's an extremely quiet and good sounding amplifier. If you wish you can read the review that Stereophile did on this amp, they liked it a lot and so do I. Note, I have this amp and am driving 6 ohm speakers without any issues, the amp will get warm when I am cranking the watts but only about 110 degrees which is quite safe and pretty normal IMO. Personally I would give this an amp a rave review, both for it's sound and the price, at this price level it's a bit of a steal. AS for your choice of the C162 I suspect that it just doesn't have enough power for those speakers you have chosen.

Next up in price is the Krell KAV-400xi. It's rated at 200 wpc into 8 ohms (continuous) and 400 wpc at 4 ohms (continuous). Cost is about 2500 USD. Stereophile reviewed this amplifier and noted an increase in noise as the amplifier got hot so providing adequate ventilation is critical. Note, Stereophile tested it at loads as low as 2 ohms so you can be sure it will deliver, however it may get a bit grainy if you push it too hard. Which really shouldn't be too likely with 92 db speakers unless you really want to go deaf. 400 watts into those speakers may have your neighbors ears ringing and I am sure the police will come calling. Keep your volume level reasonable and it'll probably sound great.

Last up is the McIntosh MA6900. It's rated for 200 wpc at 8, 4, and 2 ohms. Cost is about 5000 USD and it's what I would buy if I didn't have to worry about a budget. I have always wanted a "Mac" but never could afford one. BTW, due to the use of McIntosh's Autoformer output transformer the wattage doesn't rise as the impedence drops, it stays level. Some may consider this a deficit but this also means that this particular amplifier is rock solid stable into any load because it's basically a constant current amplifier. That means that the power supply won't ever be overloaded and that's a good thing to have when your driving a low impedence speaker. BTW, McIntosh still builds every one of their amplifiers in Binghamton, NY and they have been there since 1951, you'd have a hard time finding any other maker in high end audio with a history this long. I have also heard that McIntosh will service any amplifier that they ever made as long as they can find parts to repair it with. So if you can afford the MA-6900, it may be the last amplifier that you ever buy because it'll probably last 50 years (with regular servicing). Like me, it's probably way over your budget but we can dream can't we?

dug_junk
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Re: Amp/Preamp options are killing me...

I'll take a look a those options. I've actually done a little more digging into the Outlaw, and it looks pretty nice for the money. It also has preouts in the event I would use it as a preamp in the future. The NAD is probably on the high end of what I would want to spend right now. BTW, I got the speakers directly from Tyler Acoustics. They are trade-ins backed up by Ty, the owner/mfg. I ordered them for $2300 with a custom built pair of speaker stands. It's the most I've ever invested in any single audio component. They sound great and Ty spoke with me personally about his products and philosophy.

McIntosh sounds like my kind of company. I like the history and one day I will likely consider them if I decide to invest more money in the system. It doesn't hurt that they look pretty stylish to boot!

The preassure in my head is receding... Thanks for the advice, guys!

dug_junk
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Re: Amp/Preamp options are killing me...

I've ended up trying the Outlaw Audio RR2150. It has plenty of power. With my speakers, I usually have the volume knob pretty close to the low end for comfortable music levels. The unit hooks up real easy and supported bi-wiring without issue. The sound is better then anything I've experienced in the past with mine or my father's home stereo. I now understand what people mean my stero imaging and soundstage! I'm really pleased with the performance for the price. Definitely worth checking out if you are considering Outlaw's offering.

I also use the receiver for watching television and playing movies/games. It works great. The pre-out for the subwoofer is super convenient as is the built-in analog crossover. I believe this receiver will keep me happy for some time to come.

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